First time posting in the Site Suggestions forum.

For the past few months I've noticed that when I submit a comment, the Post Quick Reply button highlights and I get the spinning whirlwheel, but the comment never posts. Clicking the button a second time posts it immediately.

By comment, to you mean submit a repy? I've noticed too the quick reply doesn't ever work for me either, so I just stopped using it.

Yes, Quick Reply specifically. It seems like I have to click the button twice to get a reply to go through.